Turbocharged internal combustion engine

Abstract

This disclosure relates to a turbocharged low compression ratio diesel engine. An air by-pass is connected in parallel with the engine and is operable to by-pass a portion of the compressor output around the engine and into the exhaust manifold. A control is connected in the by-pass to regulate the amount of by-passed air, the control operating in response to the compressor output. The by-pass further includes means for heating the air flowing to the turbine to aid fuel combustion in the engine cylinders.

We claim: 
     
       1. Apparatus for use in a diesel engine including at least one engine cylinder, a turbine-compressor having a surge line characteristic, an intake manifold connecting the compressor outlet to the cylinder, and an exhaust manifold connecting the turbine intake with the cylinder, said apparatus comprising a by-pass pipe adapted to be connected between said compressor outlet and said turbine intake, bypass valve means in said pipe for controlling the volume of by-passed air flowing out of said compressor outlet and through said pipe to said turbine intake, sensing means for sensing the static and dynamic air pressures at said compressor outlet and for regulating said bypass valve means in response to the ratio of the static and dynamic air pressures, said sensing means including pressure ratio responsive means for regulating said volume of by-passed air to maintain compressor operation adjacent to said surge line, and a burner mounted between said pipe and said turbine intake and connected to receive both by-passed air from said pipe and exhaust from the exhaust manifold. 
     
     
       2. Apparatus according to claim 1, and further including a venturi formed in said intake manifold, and said sensing means includes a first tube connected to the throat of said venturi for sensing static pressure, and a second tube extending into the throat of said venturi for sensing the combination of the static and dynamic pressures. 
     
     
       3. Apparatus according to claim 1, and further including a check valve in said pipe for enabling by-pass air to flow only from said intake manifold to said exhaust manifold. 
     
     
       4. Apparatus according to claim 1, and further including ejector means for ejecting air into said pipe and toward the burner. 
     
     
       5. Apparatus according to claim 1, wherein said sensing means includes a movable member for regulating said bypass valve means, said movable member having one side thereof responding to the static air pressure and another side thereof responding to the dynamic air pressure, and the position of said member being a function of said ratio. 
     
     
       6. In combination, a diesel engine including at least one cylinder having a relatively low compression ratio, a turbine-compressor having a surge line characteristic, air intake means connecting the compressor with the air intake of said cylinder, exhaust means connecting the exhaust of said cylinder with the turbine, a by-pass pipe connecting said intake and exhaust means in parallel with said engine cylinder, valve means in said by-pass pipe, sensing means connected to said valve means and to said intake means for sensing the static and dynamic air pressures in said intake means and for regulating the amount of by-passed air in accordance with the ratio of said static and dynamic pressures to maintain compressor operation adjacent said surge line and a burner connected in said exhaust means and receiving both by-passed air and engine exhaust. 
     
     
       7. The combination of claim 6, and further including an air ejector in said by-pass pipe.